Apparatus for making geophysical measurements



Dec. 4, 1934.v

F. .LA G. NEUMANN Er AL APPARATUS FOR MAK-ING GEOPHYSICAL MEASUREMENTS Filed March 5, 1934 2 Sheets-Sheet 1 Dec. 4, 1934. F. J. G. NEUMANN Er AL 1,983,483

APPARATUS FOR MAKING `Gf-:OP'YSCAL MEASUREMENTS Filed March 5, 1934 2 sheets-sheet 24 lATTORNEYS Patented Dec. 4, 1934 APPARATUS Foa MAKING GEorHfYsIoAL MEAsUnEMEN'rs Franz Julius Gerhard Neumann and Werner Rudolf Haubold, Anahuac, Tex., assignors by mesne assignments, to The Salt Dome Oil CorporationHouston, Tex., a corporation of Dela- Ware Application March 3, 1934, Serial No. 713,852 15 claims. (ol. 2654-1) This invention relates to apparatus for making geophysical measurements. The invention more particularly relates to apparatus for making such measurements upon the areas of the earths surface which are covered lby water.

The methods of making geophysical measurements'onland where the portion of the earths surface upon which the geophysical instrument being used is readily accessible, are well known and understood. Such measurements have been made based on dierences in the density or of` the mass of the different materials, rocks, strata or other deposits in the earths structure. Also measurements have been based on electric conductivity, magnetic qualities, radio emanations and also upon the capacity of the structure. to shock.

The torsion balance is an instrument in common use for determinations based on differences in mass. The seismograph is used to determine the rate of transmission of shock by materials of f diierent character in the earth. For this purpose vibrations artically produced are used. In most cases the instruments used in making these measurements must be positioned in iixed relation to the earths structure or at least ilrxnlyor stably positioned with respect thereto. Particularly with instruments of the type of the torsion balance and the seismograph in which the parts are delicately mounted, it is necessary that the instrument be so firmly or stably supported and held with respect to the earths surface that accidental movement thereof shall be prevented. It also is necessary that the instrument be protected from the inuence of outside forces causing jar or vibration which wouldproduce error in the reading or prevent accurate observations being made. In the use of such instruments on land it has been possible to take such precautions without difficulty.

The use of geophysical instruments and th making of geophysical measurements upon areas of the earthssurace covered by Water heretofore have been attended with such dimculty as to have prevented extensive making of measurements of this kind in such areas. We are awarethat heretofore it has been proposed to mount a geophysical instrument on a pile driven into a penetrable bottom underlying a body of water. We are also aware of the method which has been proposed for mounting geophysical instruments in a submersible vessel so lconstructed and used as to rmly or stably position the instrumentl with respect vto the earth underlying the body of water. With the aid of such a submersible vessel it has been possible to make such measurements in depths in which it would be impractical to drive piles.

In relatively shallow depths of water in which the use of a submersible vessel is impractical or unnecessarily expensive, it has been found that geophysical instruments mounted on piles are subjected to serious errors due to forces acting upon the instrument which are the result of the motion of the water caused by currents or by the wind as well as to the wind itself. A pile or a group'of piles upon which a geophysical instrument may be supported is subject to the wave action which may produce forces of such amount as to cause vibration or jar of the instrument which will entirely prevent readings of .sumcient accuracy to be of scientic or commercial value. Moreover, when such supports or piles are positioned in currents of water, forces of like character may act upon the piles and may be transmitted to the instrument with equally deleterious effect. The effect of wind frequently is more severe as it blows across open water and the errors of observation and recording of the instrument may be produced in greater degree from this cause than is usual upon land; also it is more diicult to protect the instrument from the force of the wind by suitable housing unless an expensive structure and one not easily portable is erected upon the piles. Furthermore, a pile is unwieldy and heavy and diicult `both to fasten in the underlying bottom, and after obtaining reading, to remove therefrom and to transportto a new position.

' The present invention has for an object the provision of apparatus for making geophysical measurements uponareas of the earths surfaces covered by water which are, therefore, not readily accessible for positioning the instrument with respect to the earth in the usual manner.

It also is an object ofthe invention soto carry out the methods of making these observations and to provide suchapparatus as will prevent the entrance of substantial 'or undesirable error in the observations or readings or recordings of the instruments. y y

It is a further object of our invention to provide apparatus for carrying out these methods of making geophysical measurements which will be readily portable upon the surface of the water and whichjwithout difficulty, may be positioned with respect to the earths surface at the point where it is desired to make the measurements. Moreover, it is an object of the invention that the apparatus shall be so constructed as to shield the instrument from shock or disturbance produced by the motion of the Water or of the air. 110

the same level as that outside the oat. 'I'he dithe two members such as beams 3 and crossp beams 'I or beams 9 and cross-beam 5. Upon the lower side ofthe frame are appliedlplanks 13 extending parallel to the beams 3, and upon the upper side of the float and forming the platform floor are planks 15 laid transversely to the beams 3. The joints between the several planks 15 and the joints between the beams 9 and cross-beams 7, as well as the joints between these members and the planks 13 may be caulked in the manner which is usual in constructing a fioating vessel. 'I'he deck 15 also may be made water t ght. The construction above described is merelytypical and any suitable construction may be adopted which` will provide a iioating member capable of carrying the'working load when floating and having the proper stability, as well as the proper distribution ofthe mass thereof.

In a practical embodiment of the invention We have used a depth of iioat of about l 1/2 feet and the size of oat about 30 feet on each side. Atthe center of the iioat in the particular embed ment illustrated in Figures 1 and 2 is constructed an 'opening therethrough providing a downwardly extending'space 16 into which the water rises to mensions of this space 16 in a practical embodiment may be, for example, 10 feet on each side. Thespace 16 may be formed by the members 17 and 18 which are suitably framed with the beams 3 and the cross-beams 5 or may be formed by these beams themselves. In order to stien the structure the posts 12 are provided-in the corners which may extend below the underside of the float to provide support for a skirt or shield -19 constructed of planks 20 fastened to posts 12. The skirt 19 may extend downwardly from the iioat to any desired distance and as shown in the modification illustrated in Figure 3 may extend close to the bottom underlying the body of water.

Within the space 16 in the arrangement shown in Figures 1 and 2 is positioned a support 25 having a table constructed with a suitable frame 26 and a top 27 provided with clevis pieces 28 to which are pivotally fastened legs 30. In the particular embodiment illustrated in Figures 1 and 2 the support is provided with four legs, but such a support may be constructed in other ways and conveniently as a tripod, a particular form of which is to be hereafter described as part of our invention. I l f The top 27 of the support 25 provides a surface upon which may berested. the base 32 of a geophysical instrument. The particular instrument illustrated is a torsion balance having the usual devices for leveling and adjustment, which in themselves form no part of the present invention. The table 27 provides a surface or a bearing which may be so formed that any instrument which it may be desired to use may be set thereon.

For more ready access to the instrument itself, while leaving ample space around the legs 30 of the support 25, the deck or floor 15 is extended over the space 13 and supported on brackets 21.-

`that the size of the opening 16 and the amount of clearance shall be such that the movement of the float caused by water currents or action of wind and wave on the float will not bring the float into contact with the support 25 or the instrument 32. 'I'he opening, however, should be so restricted that from the platform around the opening the workman may set the support 25 on the bottom underlying the water, may suitably adjust it in operating position and may set thereon and adjust the geophysical instrument being In Figure 1 is shown also a housing 35 having an access door 36. Said housing may be fastened by suitable fasteners 38 `upon the deck or iioor 15 of the iioat 1.- This'housing not only serves as a protection for the instrument from the.

weather and from spray butv shields the instrument from the force of the Wind which might cause disturbance thereof. By thus shielding the instrument error in the observations and registrations of the instrument is reduced or prevented. 'Ihis housing also serves to keep the temperature of the instrument more nearly constant.

The modification shown in Figure v3 illustrates a platform capable of floating and of being transported upon the surface of the water similar to the construction of Figure l. Instead of anchoring the iioat by means of cables 23 as in Figure 1 struts or supports 40 may be used and may be fastened by fasteners 4l to the structure of the oat at the sides or edgesl thereof. These struts may be driven into' the bottom underlying the Water to a point where the upper ends thereof become suitably positioned for engagement with the side of the iioat and then may be fastened thereto in a convenient manner. By providing a slot 42 in the upper end of the strut through which .the fastening means may pass we may adjust the strut for different depths of water while being able to drive the lower end of the strut into the bottom sufficiently to provide not only the support for the platform but to securely hold it in position when fastened to the struts.

As above referred to, the skirt 19 in the embodiment of the invention shown in Figure 3 may extend to a point near the bottom or to any desired depth. This skirt encloses a space 16 within which the support 25 may be positioned with the legs thereof driven or pressed into the bottom underlying the water in the manner described in platform, being positioned to the struts 40 is prevented from pitching and rolling under wave action and a stable platform may be secured upon which a shelter 43 may be erected which may be in the form of a tent with sloping sides supported by a suitable frame 45. By sloping the sides as shown, the action of the wind upon the structure and uponl the noat is thereby-decreased.

While in some cases the construction illusftrated in Figure 3 may be preferable, the construction illustrated in Figure 1 in most cases prevents the action of the waves from reaching the support 25 and the instrument 32 and provides a quiet surface and a quiet mass of water within the opening 16.- Moreover, the size and mass of the sont may be auch that while it may be easily transported or towed from place to place, nevertheless it may have such mass and such extent upon the surface of the water as to reduce the pitch or roll of the iloat to the degree where even with considerable force and height of the waves a substantially quiet water mass is maintained within the opening 16 of the float. Moreover, by suitably constructing the skirt 19, the surge of wave action or the vibration caused by currents owing by the legs 30 of the support 25 may be reduced or eliminated.

It will be apparent from the above description of our invention that the apparatusand construction herein disclosed particularly are adapted for use inmaking geophysical measurements on areas of the earths surface which are covered with water to a depth such that from the surface of the water the bottom may be reached by structures or struts which are convenient to handle and which may have their lower ends forced into the earth so as to x the strut with respect to the earth while extending up through the water to a point adjacent the surface so that the geophysical instrument may be supported thereon.

While the invention is not limited to particular depths of water and while theprovision of a shield against wave action and against water currents as well as against wind for a geophysical instrument mounted upon a support set in the water may be utilized within lpractical limits regardless of the depth of the water,-in general we consider that our invention has particular application in depths of water from about 2 to 20 feet. Bodies of water having a. depth of 2 feet or greater and particularly when exposed in open extents to the force of the wind, may develop considerable wave action and it becomes necessary to shield the instrument against the force of such waves. Moreover, in order to secure readings over a sufficiently large area the apparatus -must be transportable. We therefore have devised the oat, above described, constructed to provide the shield for the instrument and for its support. In depths of water, however, extending to say 20 or 30 feet it is still possible to reach the bottom with struts to hold the platform or support for the instrument which may be driven into or otherwise fixed in the bottom by working from the floating platform, provided that these struts and supports are suitably constructed.

In order to provide a support which may be used in any depth of water in which it is possible to reach the bottom with a, member in the form of a strut, we have devised a frame or structure which may be assembled in place in the vspace 16 or in some cases may be inserted therein after assembly. The depth of the water in which the support is to be set and the question of convenience may determine which method is to be adopted. We have provided in this support,-

however, .for fixing the lower ends of the strut members thereof in the earth bottom underly-l ing the body of water and for securing a high degree of rigidity of the structure of the support, so as to further reduce the possibility of disturbance of the instrument by exterior forces. Moreover, the construction of the support is such that it may easily be assembled without the use of partisular apparatus and the strut members thereof mastit'v fastened into the earth bottom with the use'fh d tools only.

Ini'igu" shown a vertical section through the suppri? ro'ur invention. The legs 50, of

utilized in the particular emted .in Figures 3, 4, 5, 6 and 7, pipes. In this particular embodiment these pipes may be -of about 2" nominal pipe size, having an outside diameter of about 2%". As will be understood from further d'escription oi' the device, the legs 50 are driven into or otherwise xedly positioned in the earth bottom 2 underlying the body of Vwater and are inclined to each other and converge upwardly t0- ward each other. As may be seen from Figures 5 and 7 they are spaced apart, symmetrically in the particular arrangement illustrated, around a common axis.

In a vertical position generally coincident with said axis is provided a shaft or elongated hub 52 from which project two sets of arms spaced apart along said shaft or hub and `in each set an arm extends generally laterally from the axis toward each of the three pipes. Adjacent the lower end of the shaft 52 the arms 54 project in an upwardly inclined direction to connect said shaft with three collars 56 provided with funnel like portion 57. These collars have holes therethrough somewhat larger than the outside diameter of the' pipes 50. The arms 54 hold these collars 56 in such position that the axis of the holes therethrough has the same general inclination in which it is intended that the pipes of the tripod shall become positioned when xed in the earth bottom and held in proper position to support the base of the geophysical instrument 32.

The upper set of .arms 58 are similarly rigidly 105 connected to the shaft or elongated hub 52 and extend in a slightly upwardly inclined direction to jaws or clevis pieces 60. These: clevis pieces 60, which may be open at the outside portions thereof as shown in Figuresl 4, form guides through which the pipes may be slid when inserting them in position, as will be hereafter described. The arms 54 and 58 and the shaft or' hub 52 form a rigid frame 55 which it will be clear from a consideration of the drawings and the above description, may be held by the three pipes extending through the collars 56, the outermost. portion of the inner surface of the hole ofthe collar bearing against the outermost surfaces of the respective pipes 50, the clevises 60 sliding along the pipes until further movement is arrested by the collars 56 resting against the pipes. On the other' hand, the frame may be lifted in a direction of the axis of the shaft 52 until the collars are substantially clear of the pipes 50. If

, held in such position by some means, as hereafter described, 'the pipes 50 may be slid lengthwise thereof through the open space of the clevises 60 and through the openings in the collars 56.

In Figure 4 at 'I0 is shown a hub having con- 130 nected thereto, to form a rigid frame or spider 7l, arms 72 extending outwardly from the hub 70 to engage the pipes 50. In the embodiment of our invention illustrated in Figures 4 and 5 these arms 72 are formed adjacent their outer ends with 135 portions 74 extending part Way around the pipes 50. Also rigidly fastened to the arms 70 by suitable fastening means 76 are hinge bearings 78 having hinge pieces 80 pivoted therein upon hinge pins 82. Thehinge pieces 80 may, therefore Abe swung away from the pipes 50 or may be swung against the pipesl 50 in a generally parallel position to the portion 74 of the arms '72. The hinge pieces 80`have pivoted adjacent their outer ends swing bolts 84 upon which may be screwed wing nuts 86. In the portion 74 of the arms 72 which contact the pipes 50, a slot 88 is provided in which the swing bolt 84 may be slipped when the hinge piece 80 is to be clamped around the pipes 50 and the wing nuts 86 may then be 150 screw 96 isa collar 98 fitting within the recess of the hub '70. The shank 94 and the 'collar 98 fastened thereon are free to tum in this recess with the turning motion of the jackscrew 96 upon its axis. Thus it will be seen that the jackscrew is held in operable relation with the frame or spider 71 provided by the hub 70 and the arm 72 so as to receive the thrust of the jackscrew in an upward direction while holding the jackscrew from dropping out of engagement withthe spider. In the shaft or h-ub 52 is cut a thread 100 fitting to the thread of the jackscrew 96. Also fastened upon the shank 94 of the jackscrew or forming anintegral part thereof is a collar 102 havingholes 103 therein to receive a wrench bar for the purpose of turning the iackscrew on its axis.

It will be clear from a consideration of Figure 4 that when the. jackscrew'96 is screwed out of lbe moved away from the frame 55 formed by the v the thread 100 in the shaft 52 the collar or flange 98 will be moved upwardly against the inner wall of the rece'ss in the hub-70 and the hub 'l0 will arms 54 and58 connected tothe shaft 52. On the other hand, ifthe spider 7l is held in a fixed position the frame 55 will be moved away from the spiderl '71 when the. jackscrew 96 is screwed out of the thread 100. Reverse movements of the parts will be secured by opposite turning motion applied to the jackscrew 96.

If the spider 71 is clamped upon the-legs 50 by the, hinge pieces 480 held by the clamping force of the wing nuts 86 and swing bolts 84, then upon turning the jackscrew 96 out of the thread -100 the arms 54 will be forced downward in a direction axially of the shaft 52. The inner surface of the outer portion of the collars 56 will move into contact with the outer portions of the respective pipes and further turning motion of the jackscrew 96 willcause these collars to bear hard upon these pipes. Because of the inclination of the pipes and of the inner surfaces ofthe collars and because the motion applied to the collars is in a direction parallel to the axis of the shaft 52,

a jamming or wedging action of the collars upon the pipes 50 will occur. As the spider formed by collars 56, the arms 54 and the shaft or hub 52 are parts of the rigid frame 55, further motion of the :frame 55is stopped upon wedging of the collars upon'the pipes 50. The pipes are rigidly gripped by the spider and are held in fixed and rigid connection with each other at the portion of the length thereof contacted by the collars 56. As `the upper ends of the pipe 50 are rigidly held in the spider 'I1 and as the shaft 52 and the jackscrew 96 form a stiff connection .between the spider '71 and the frame 55 including the arms 54 and the collars 56, the whole-supportlthus becomes a rigid unit. 'When the lower ends of the pipes 50 are suitably fixed in the earth bottom underlying the water, a rm .and rigid support is thus provided for the geophysical.. instrument mounted upon the upper ends of the. structure and one which will withstand .the forces caused by motion of the lwater' either due to currents or wave action and one which will withstand .the j shock which may be accidentally applied thereto by contact with the float by the workmens tools or from other external sources.v

In order to flxedly position the pipes in the earth bottom underlying the body of water, we may drive the pipes into penetrable material in said bottom to a depth sufllcient to secure a rigid and firm support for these pipes. It is important in using some geophysical instruments, such as the seisrnograph,` to insure that an intimate and firm contact with the earth is secured in order thatthe articially generated earth shock may be properly transmitted to the instrument through the structure. In some cases in order to secure the desired firmness and contact with the earth, we have found that it is desirable to drive or otherwise force the legs or struts, especially when using pipes such as those described above, into the solid earth bottom underlying the water to a depth of 3 to 4 feet. We have so devised our support that We may drive these pipes to any de-v sired depth and may form the pipes or legs 50 in sections as indicated in Figure 4, of such length as may be conveniently handled and, by coupling ,sections together, tok provide suflicientv length reachinginto the firm earth bottom underlying the water.

In this connection, it should be explained that in many localities a firm penetrable earth bottom underlying bodies of natural water is overlaid with a layer of slit or semi-liquid. mud or ooze below 'the water and incapable of bearing weight or of holding a structural member in xed position in relation to the earth bottom.l Thus it'is necessary in many cases not only to provide a strut which is sufliciently light in 4weight to be.

the work of xing and rmly positioning the struts l or legs of the tripod or support of our invention by so constructing the legs that instead of driving them directly into the underlying earth oor they may be inserted therein by a turning motion. In order to accomplish this result we may provide at that end of each leg which is to be inserted in the earth, a screw member 110 which may be fastened to the'end of the pipe 50 and may project beyond the end thereof. The screw member 110 may be formed as a helical coil. As s an example of a convenient construction which may beutiiizedwith pipes such as the 2" pipes referred to above, we have formed the helical coil by winding a piece of steel I/g" in diameter upon an axis to form a helix having a diameter of about 2" with a pitch of the degree of 3/4" to 1" from `one turnl of the helix to an adjacent turn. There is thus formed a member similar to a corkscrew which, upon turning the pipe 50 upon its axis, will draw -the pipe secured thereto downwardly into the earth as the screw member 110 is screwed into the earth. In order to effect this turning motion we nnd it merely necessary to turn the pipes' with a Stillson wrench or with a wrench of other convenient -type applied to the upper end of thepipes.

While, as stated above, we may assemble the parts illustrated in and described in connection with Figures 4 to 7 inclusive prior to setting the support upon the bottom, which method of utilizing the device of our invention may be most convenientY in some cases,for the most part, in View of the necessity of securing the pipes 50 at sufficient depth inthe penetrable earth bottom, and in some cases lat diderent depths, we have found yit preferable to assemble Ythe support in position within the opening i6 ofthe float l' described in connection with Figure l. In order to secure the advantage aiorded by the cievises 60 and collars 56 attached to the frame 55 to guide the pipes into the proper positions in the earth bottom, not only with respect to each other but with respect to the neat, we may temporarily support the spider 7l upon a planlsor bar set across the opening 16 so that it may be held in'approximate Workdng position in relation to the oat. The arms 54 and 58 will thereby be held in hired relation to the oat, the shaft 52 being suspended -by the Vjaclrscrew 96 supported by the collar 98 bearing against the ange of the hub 70. By so temporarily supporting the spider 7l, the hinge pieces 80 may be swung upon the hinge pins 82 away from their clamping position. The pipes 50 then may be passed down through the respective clevis pieces 60 and through the respective collars 56,the funnel-like portions 57 serving" to guide the pipes 50 into the collars 56 and the collars 56 and the clevis pieces 60 acting as guides to direct the end of the pipe 50 and the screw member 110 attached thereto to the proper point at the earth bottom which is in line with the collars 50,'the clevises 80 and the clamping devices 74 and 80 of the spider 71. y

If the helical screw member 110is not used, the pipes may be driven directly into the earth bottom by force supplied to the upper end of the pipes. Moreover, as the pipe is driven down into V the earth additional sections may be added at the upper .end of the pipe, it only being necessary that the coupling members be of such form as will pass down through the clevis pieces 60 and the collars 56. When, however, the screw member 110 is utilized, the pipe may be turnedin the collar 56 and in the clevis 60 and thereby screwed into the earth bottom to the desired degree, further sections being added to the pipe if necessary. Combinations of driving the pipe and screwing it into the earth bottom may be used in certain cases depending upon the character of the structure ofthe bottom into which the pipes are to be driven. Y i

When the pipes have penetrated to suilicient depth to give ailrm and rigid support to these pipes and to position the upper ends thereof adjacent the water level, and preferably above the water level, the spider 71 may be clamped to the upper ends of these pipes by swinging the hinge members 80 into clamping position and fastening them by means of the wing nuts 86. The temporary support for the spider 71 may then be removed, the weight of the frame 55 being thereafter suspended upon the Jackscrew 96. If,

v now, the :Iackscrew 96 is turned in a direction which will screw it out of the thread Y100 in the shaft 52, as above desoribedfthe collars 56 will move downwardly in the direction of the shaft 52 and will bind upon the inclined pipes 50. The force thus applied will tend to draw pipes 50cmwardly toward the axis of the shaft 52 until they bear against the inner surface 81 of the clevis pieces 60 on the arms 58, the upperY ends of the pipes and the ends fixed in the earth respectively being held in fixed relation to each other. It thus will be clear that by using the downward motion of the spider arms 54 and collars 55 it is not necessary to provide collars for the arms 58, as no bearingY outwardlyy from the'axis upon clevis pieces 60 occurs. lThus the pipes maybe easily slipped into the clevis pieces.

If for any reason, however, the reverse motion. of the screw 96 is preferable, collars may be used in place of the clevis pieces l60 and the upward movement of the collars 56 will tend to move the portions of thefpipe passing therethrough outwardly from the center axis of the support and cause the portions of the pipe adjacent the arms 58 to move outwardly and bear against the col` lars which, in that case, ,would surround the pipes 56 and be attached to the arms 58. In either case it will be understood that the rigidity provided by the central'shaft or hub 52 and its arms 5d and 58 is transferred to the otherwise free portions of the lengths of the pipes 50 between the upper ends thereof and the earth biottom.

By suitably proportioningthe arms 5e and 58 of the frame 55 in relation to the shaft or hub 52, the push and .pull forces, as well as the bending forces which are applied to the members of the frame 55 and the spider are withstood. In the particular embodiment of the invention with which pipes of the size of about 2" pipe size are utilized, the shaft or hub 52 may be of about 4 diameter and about 5 feet long. The arms 54, as shown, may be fastened adjacent the lower end of the shaft 52. Adjacent the center of the length of the shaft 52 the arms 58 are fastened. When the structure of the frame 55, for example, is built of iron the arms 54 and 58 may be welded to the shaft 52 and may be formed of flat iron bars of about 3 to 3%" depth by to l" thickness. The jaclp- 115 screw may be of about 15/2" diameter and cut with six threads per inch and of a form which is usual in jackserew design. The arms 72 of the spider 71 may be of material of similar size to the arms 58 and may be welded to the hub 70 120 and to each other at the point of joining the hub to form. a. rigid spider.

A modified form of the legs 56 of'our .support is shown in Figure 6. As 'will be seen ,from this figure, within the pipe 50 is inserted a. shaft or rod 120 having a bearing 122at the upper end thereof and provided with a bearing 123 at the lower end thereof. In some cases, a shaft 120 of uniform diameter from one end to the other thereof may be passed through-thepipe. At the lower end of the shaft may be fastened the screw member 110. The pipes 50,.therefore, may be clamped rigidly to the spider 71 and the shaft 126 may be turned, as with a wrench applied to the head 124 at the upper end thereof, to` 'screw the screw member into the earth bottom thus to draw the shaft down through the pipe 50. It will be understood that the pipes 50 may be driven Dart way into the earth bottom or all the l way, the screw member being screwed into the 140 earth bottom to secure the additional hold after driving the pipes. On the vother hand, the shaft may project beyond the pipes 50 and these pipesmay reach, for example, down to the earth bottom and provide a guide for the shaft extending beyond the ends of the pipes into the earth to the desired depth. In any case the shaft 120 is so mechanically `fitted to pipe 50 as to hold said piperlsidly and firmly in position when the lower end of the shaft is xed to the bottom.

no v

i to transmit thereto the rigidity of the spiders.

Moreover, within the scope of our invention, by using suitable jackscrews between the parts, the fixed or clamping spider may be intermediate between the other two binding or jamming spiders. Conceivably also, in certain cases, the second spider, such as that provided by the arms 58 and the clevis pieces 60, may be eliminated and the jamming or binding of the pipes may be effected by motion of a spider such as that provided by the arms 54 and the collars 56 which is movable away from or toward the clamping spider 71. In such case, however, the pipes 50- should be of such size with respect to the free length thereof as to act with the jamming or wedging spider to produce a rigid support, as in such case the forces transmitted to the pipes by the arms 54 may act merely against the bending -spect to said instrument as substantially to intercept motion of the water and to prevent disturbance due to motion of the water from reaching said instrument.

2. Apparatus according to claim 1 in which said shield is extending downwardly into the water sumciently to prevent disturbance being transmitted through said support to said instrument. 3. Apparatus for making geophysical measurements upon areas of the earths surface covered by water which comprises a support of a form capable of being fixed tothe bottom underlying the water and extending to a point above the level of the water, a geophysical instrument mounted on said support above the water level, and a member held against substantial movement with respect to the earth and constructed so to surround said geophysical instrument vas to shield said instrument from forces caused by motion of the water. v

4. Apparatus for making geophysical measurements upon areas of the earths surface covered by water whichl comprises a support of a form capable of being fixed to the bottom underlying the water and extending to a point above the level of the water, a geophysical instrument mounted on said support bove the water level, and a member oating upon the surface of the water and anchored to prevent substantial motionhthereof over the surface of the water, said floating member being constructed to surround but to oat clear of said instrument when so anchored and being constructed to shield said instrument from forces caused by motion of the water. 5. Apparatus for making geophysical measurements upon areas of the earths surface covered by water which comprises a float providing a "workingrplatform said float having a centrally located opening therein surrounded by a submerged portion of the structure of the floaty and providing a clear space in the direction toward the bottom underlying the water, a support extending downwardly into the water through said space 'and clear of the structure of the float and having its lower: end fixed in the bottom, said float being constructed with suicient mass to absorb when anchored the impact of waves and the motion of the Water to prevent the force there- -as toprovide a clear space extendingdownwardly through which from the platform a support of suillcient length to reach the earth bottom underlying the water may be fixed in said bottom with the upper end accessible from the platform around said opening but free from contact with the platform, said platform being of such massl and of such form as to shield from the impact of forces caused by motion of the water said support and a geophysical instrument mounted thereon.

7. Apparatus for making geophysical measurements upon areas of the earths surface covered by water subject to motion with respect to the earth which comprises a support of a form cap-- able of being fixed to the earth bottom underlying the water and arranged to` support a geophysical instrument mounted thereon, and a shield positioned with respect to said instrument in the direction from which the water is moving.

. 8. Apparatus for making geophysical measurements upon areas of the earths surface covered by water which comprises a support of a form capable of being fixed to the earth bottom underlying the water and arranged to support a geophysical instrument mounted thereon, and a shield so constructed and so positioned withrespect to said support as substantially to intercept motion 'of the water and to prevent disturbance due to motion of the Water from reaching said support.

9. Apparatus for making geophysical measure- .ments upon areas of the earths surface covered by water which comprises a support of a form capable of being fixed to the earth bottom underlying the water and arranged to suppprt a geophysical instrument mounted thereon, and a member free of connection to said support so as to be incapable of transmitting thereto forces due to motion of the water received by said member and providing a shield so constructed and so positioned with respect to said support as substantially to intercept motion of the water and to prevent disturbance due to motion of the water from reaching said support.

l0. Apparatus for making geophysical measurements upon areas of the earths surface covered by water which comprises a support of a form capableof being fixed to the bottom underlying the water and extending to a point above the level of the water, a geophysical instrument mounted on said support above the water level, and a member oating upon the surface of the water and anchored to prevent substantial motion thereof over the surface of the water, said floating,

member being so constructed andv so positioned with respect to said instrument as substantially sov to intercept motion of the water but to float clear of scid instrument when. so anchored so es to shield seid instrument from forces concomitontly occurring with motion of the water.

il. Apporotus for making geophysical measurements upon :crees of the earths surface covered by Water which comprisese support of a form cepable of being hired to the earth bottom underlying the writer und to support a geophysical instrument mounted thereon, a. platform held against substentiei movement with respect to the eerth, seid plotiorin beine' so constructed 'und being so positioned with respect to seid support as to provide access to seid instrument while being so positioned with respect thereto as substantially to intercept motion of the water and to prevent disturbance due to seid motion from reaching said instrument.

12. i plotiorni for use in rushing geophysical measurements upon crees or the eerths surface coveredby weiter. seid pletforrn being constructed so as to be supported odjacent the water surface and so es to be heid egroinst ,substantiel movement thereof in c. piane psrellei to the water surface, seid platform being constructed to beer the weight of observers when so supported, and being of such form that when positioned with e. port thereof in o position with respect to s geophysical instrument mounted upon o support xed in the earth bottom underlying the water such as will intercept motion of the water toward said instrument, said part provides a shield preventing disturbance due to motion of the water from reaching said instrument.

13. A platform for use in making geophysical measurements upon areas of the eerths surface covered by water, said platform being constructed so as to be supported adjacent the weiter surface and so as to be held against substantial movement thereof in a plane parallel to the water surface, said platform being constructed to bear the weight messes of observers when so supported. and being of. such form that when positioned with a. part thereof in aposition with respect to a. geophysical instrument mounted upon a. support fixed in the earth bottom underlying the water such as will intercept motion or the water toward said instrument, said port provides o. shield preventing disturbance due to motion of the water from reaching said instrument, said platform being provided With a barrier extending downwardly therefrom toward the bottom and arranged to shield seid support.

14. Apparatus for picking gciophysical measurements upon areas of the earths surface covered by water which comprises s support of a form capable of being fixed to the earth bottom underlying the water and arranged to supporta geophysical instrument mounted thereon, and o shield so constructed ond so positioned with respect to said support as substantially to intercept forces caused by motion ofthe Weiter und by the Wind to prevent disturbances due to seid forces from reaching said instrument.

15. Apparatus for mairinsr geophysical measurements upon areas oi' the earths surface covered by water which comprises a. support of a form capable of being xed to the earth bottom underlying the water and arranged to support a geophysical iristrument mounted thereon, and a, member free of such connection to said support es would cause transmission to said support of forces concomitant with motion of the water and received by said member, said member providing a shield so constructed and so positioned with respect to said support as substantially to intercept the forces caused by motion of the water and by the wind to prevent disturbances due to seid forces from reaching said instrument.

FRANZ JULIUS GERHARD NEUIWANN. WERNER RUDOLF HAUBOLD. 

